The 1999 International Radiopharmaceutical Symposia will be held at Washington University Medical School, St. Louis, MO, from June 24- July l, 1999. The three major international symposia of the radiopharmaceutical sciences had previously been held biennially at separate times and at separate locations. This meeting represents the first of its kind in this field, providing an unique forum for the conjoined and concurrent meeting of these three international symposia: the 13th International Symposium on Radiopharmaceutical Chemistry, the 11th International Symposium on Radiopharmacology, and the 8th Workshop on Targetry and Target Chemistry. The conjoined symposia will bring together approximately 600 investigators, post-doctoral fellows and students. Topics for discussion will involve recent advances in the areas of radiochemistry and synthetic chemistry as relevant to new radiopharmaceuticals, a forum for problem solving directed toward state-of-the-art methodology in radioisotope production, and recent advances in the study of the absorption, distribution, metabolism and excretion of radiolabeled compounds in living systems by exploiting pharmacokinetic analysis to noninvasively map and ultimately quantitate biochemical functions within the whole organism. This proposal requests funds to provide partial support for travel and subsistence expenses for invited participants, minority faculty and young investigators from North America and overseas. These symposia will be timely and important meetings in an area that has generated recent excitement because it will provide a format that brings together investigators whose collective approaches encompass radiochemistry, pharmacology, biochemistry and cell biology methods that address central issues in the mapping of molecular functions in vivo through imaging. This conjoined International Radiopharmaceutical Symposia format will provide an unique environment that should encourage informal and open discussion among the participants in a way not previously possible and this in turn will foster cross-fertilization and initiation of collaborative efforts to stimulate future research directions.